1. Field of the Invention
This invention relates to flange protectors, and more particularly to a lightweight, weather resistant corrugated plastic flange protector adapted for temporary application to the flange of a pipe, valve or other conduit so as to protect the machined surface of the flange from damage during shipment and handling.
2. Discussion of Related Art
Flange protectors are known in the art for covering and protecting pipe flanges of the type having a machined flange surface and bolt holes that extend through the flange surface and open to a back surface opposing the flange surface. For example, see U.S. Pat. Nos. 5,265,752; 4,799,716; 3,942,681; 3,856,050; 3,563,277; 1,903,220; and British Patent 757,447. While these prior art flange protectors are suitable for ideal conditions, they are manufactured from relatively expensive, heavy and weather prone materials that result in overall higher costs. In addition, prior art flange protectors made of hardboard or cardboard covers are particularly susceptible to rough handling in wet weather since protectors made from these materials can often tear away from retaining bolts or clips.
A prior art solution to counteract wet weather was to manufacture the flange protectors from high density solid plastic and polystyrene. See for example, U.S. Pat. Nos. 3,856,050 and 3,563,277. These materials, however, lack adequate shock absorbing qualities.
Alternatively, pipe ends have been known to be protected by using a fabric and paper bonded together with a water proof material as shown in British Patent 757,477. This type of protector requires substantial assembly time and multiple parts.
In addition, prior art flange protectors have been made with impact resistant material such as solid rubber, polyethylene (U.S. Pat. No. 5,265,752), silicone (U.S. Pat. No. 4,799,716); and styrofoam (U.S. Pat. No. 3,942,681). In still yet another alternative, another prior art solution provides a multi-layered flange protector having a metal shell with a compressible material (U.S. Pat. No. 1,903,220).
In summary, prior art cardboard or hardboard flange protectors fail to display adequate weather resistant properties. In addition, while the solid plastic prior art flange protectors may exhibit acceptable weather resistance, they lack sufficient impact resistance and are heavy and expensive to manufacture. Finally, while the solid rubber flange protectors demonstrate some impact resistance, these designs fail because they easily disintegrate, require an expensive solid construction, and are heavy.